Electrocardiograms (ECG) are commonly used to generate data on the health and operation of a patient's heart. A number of electrodes are attached to a patient for an extended period, typically 12 to 48 hours, to measure the cardiac impulses of the patient. The resultant data can be graphed over time to create complex curves representing individual heartbeats. These beats can be reviewed, analyzed and categorized into normal and abnormal beats. This monitoring procedure, often referred to as Holter monitoring, is described in detail in a text entitled "Ambulatory Electrocardiography-Applications and Techniques" by Susan L. Horner, published by J. B. Lippincott Company, ISBN 0-397-50586-8, and references cited therein which are hereby incorporated by reference.
The Holter monitoring process generates too much data to be efficiently or effectively analyzed in real time. There simply is not time for clinicians or physicians to review 24 hours of data. As a result, computerized systems have been developed to aid clinicians n reviewing and analyzing Holter data. Existing systems, however, have not provided clinicians with flexible, efficient and accurate means to review and analyze Holter data.